No-break power supply with an electrical machine and a flywheel

The device has an electrical machine operable as a generator or motor. The machine has a flywheel coupled to the rotor via a variable ratio coupling and a control arrangement that holds the revolution rate of the machine acting as a generator with kinetic energy stored in the flywheel constant at least over a range of flywheel speeds. The coupling arrangement has an unbranched variable ratio mechanical gearbox. The device has an electrical machine (2) with a rotor (3) operable as a generator or motor for connection to a load to be supplied with alternating current without the introduction of a variable input frequency inverter. The machine has a flywheel (7) coupled to the rotor via a variable ratio coupling and a coupling ratio control arrangement that holds the revolution rate of the machine acting as a generator with kinetic energy stored in the flywheel constant at least over a range of flywheel speeds. The coupling arrangement has an unbranched variable ratio mechanical gearbox (5).